How a Hydrogen Fuel Cell Works
H₂ input Hydrogen enters
O₂ input Oxygen enters
Electricity External circuit
H₂O output Water + heat
ANODE Hydrogen in
H₂ → H⁺ + e⁻
PEM Protons cross
Electrons blocked
CATHODE Oxygen in
H⁺ + e⁻ + O₂
OUTPUT Water
+ heat
Hydrogen Protons Electrons Oxygen Water